Reverse Brick Veneer Design

Reverse Brick Veneer Design

Because of the previous research on autoclaved aerated concrete and thermal mass, and the case study, we now have enough information to start our own RBV design. We have managed to recycle several pieces of timber, weatherboard, plywood board, corrugated roof sheet and a window. Considering the materials we have at hand, we made the design as illustrated in the diagram below.

Diagram 04. Reverse Brick Veneer Design

The wall we are going to make is a reverse brick veneer with corrugated roof. Layers from interior to exterior are listed below:

1. Hebel wall: As it was found from previous study, autoclaved aerated concrete provides better thermal mass property. We decided to use Hebel as a substitute for traditional bricks. The specific product we will use is the Hebel Block of 600L x 200W x 200D from previous research on Hebel product range.

2. Cavity: This is one of the key elements of the insulation, the same as the gap in common brick walls. The width of cavity is designed to be 40-50mm and may be changed on site in case of material limitation.

3. Timber framing: The timber framing with standard top plate and bottom plate will serve as load-bearing structure as it does in common brick veneer construction.

4. Cladding: 20mm weatherboard will be used as external cladding to protect the internal structure from external weather condition.

Additional information about the RBV design:

1. The 20mm plywood will be levelled and placed at the bottom to serve as a base for the RBV construction.

2. A corrugated sheet roof will be installed on top to protect the entire structure from water. It will be fixed to the top plate of the timber framing and the batten on top of the Hebel blocks.

3. The roof batten will be fixed to the Hebel blocks.

4. The amount of Hebel blocks needed is calculated and indicated in the diagram. We have made this design to minimize the amount of Hebel blocks that needs to be cut so we can have less building waste. As the window we have does not fit into whole block(s), two and half pieces of Hebel blocks have to be cut in such way to accommodate the window and hence waste cannot be avoided.

5. The window will be framed with the 20mm plywood first and then put onto the wall.

Construction Plan

The construction process we estimated as following:

01. Level the plywood board as a base.

02. Mix the cement.

03. Cut Hebel block Number 3, 7 and 9 into half.

04. Lay the first course of Hebel block – Number 1, and 2, and 3.

05. Lay the second course of Hebel block – Number 3, 4, and 5. Line up both ends to the first course.

06. Lay the third course of Hebel block – Number 6, 7, and 8. Line up both ends to the second course.

07. Put up temporary sheet bracing to support and stabilized the wall and wait for the mortar to set.

08. Trim the existing redundant window framing.

09. Cut the plywood into suitable sizes for new window framing.

10. Assemble the new window frame and fix the window onto the framing.

11. Cut the timber into designed sizes for timber framing.

12. Assemble the timber framing and fix it onto the base plywood board at desired location.

13. Remove temporary bracing and install the window, fix the window frame onto both the timber frame and the Hebel block wall.

14. Lay the fourth and fifth courses of Hebel block – Number 7, and 9 for the fourth, and Number 9, and 10 for the fifth. Apply mortar between the Hebel blocks and the window frame.

15. Cut the remaining Hebel blocks into suitable sizes to accommodate the window frame.

16. Lay the last course of Hebel block – Number 10, 11, and 12.

17. Cut the timber into suitable length and fix it onto the top of the Hebel block wall (as the roof batten).

18. Put up temporary bracing again to support the wall and wait for the mortar to set and the structure to stabilize.

19. Cut weatherboards into suitable length, and nail them onto the timber frame with certain overlaps (overlap to be determined on site).

20. Cut the corrugated roof sheet into desired length and fix it onto both the timber frame and the roof batten.

21. Seal any gap around window frame with silicon.

22. Put up temporary bracing to support and stabilize the entire structure till the water testing.